Impact fuse assembly



P 23, 1969 J. 1.. VANOVER v 3,468,256

IMPACT FUSE ASSEMBLY Filed D60. 4, 1967 M I E 0 54 5 32 James L. l/anaver INVENTOR.

BY MC. MULLER R0) MILLER ATTORN E YS 3,468,256 IMPACT FUSE ASSEMBLY James L. Vanover, China Lake, Calif., assignor to the United States of America as represented by the Secretary of the Navy Filed Dec. 4, 1967, Ser. No. 687,856 Int. Cl. F 42c 1/00 US. Cl. 102-73 2 Claims ABSTRACT OF THE DISCLOSURE An improved acceleration arming fuze for rockets operable at low angles of obliquity to soft targets such as water or marshes wherein the improvement comprises a newly shaped fuze housing and a defonmable cup shaped member having a fiat forward surface of considerably increased area which is readily crushable, thus rendering the firing pin operable.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

Background of the invention Patent 2,948,219 discloses an acceleration arming fuse, utilizing an unbalanced rotor, which is rotated to an armed position in which a percussion primer and a powder train are aligned between a stab type firing pin and a booster charge, the latter detonating a war head. The principal original use of the missile employing this fuse was in air-to-air warfare wherein the target was relatively hard and impact occurred at relatively high angle of obliquity. When used against targets which were impacted at small angles of obliquity, however, and particularly soft ground targets such as water, marsh or mud, the firing pin was found to be inoperative to stab the primer, probably due to the structural integrity of the fuse ogive adjacent the firing pin.

Summary of the invention The prior art referred to is modified by the present invention by the provision of a newly shaped fuse housing and a deformable cup shaped member having a flat forward surface of considerably increased area which is readily crushed at a slight angle of obliquity with a target, thus rendering the firing pin operable under such conditions as well as under high angles of obliquity.

The prior art is further modified by the use of an instantaneous powder charge in the fuse rotor and booster charge, together with improvements in a hermetic heal for the booster charge.

Brief description of the drawing The figure is an enlarged central section through the subject of the invention, like FIGURE 1 of the patent referred to.

Description of the preferred embodiment Ogive is interchangeable with the ogive of the patent referred to and is modified to provide a forward cylindrical end 12 of considerably larger cross section. A circular cup shaped member 14 is swaged onto end 12 and its rear edge is rolled or spun into a cannelure 16 to provide a hermetic seal to prevent entry of moisture. Prior to the swaging operation, a disc 18, carrying a firing pin 20 riveted to the dis, is inserted in the cup and a plurality of dimples 22 are depressed in the cup to retain the disc and firing pin in a fixed position relative to the cup.

The booster 24 comprises a cup shaped member having a wall 26 threadedly engaging the fuse body and an integral burstable end wall 28, and containing a charge of CH Its for-ward end is closed by a disc shaped closure 29 having a central cup 30 affixed to it and containing the same charge material. A washer 32 abuts fuse base 34 and a cup shaped diaphragm 36 abuts the washer and the forward end of the booster assembly, an O-ring 38 being disposed within a chatnfer 40 on the for-ward end of wall 26 which forms a seal to prevent entry of moisture.

The central portion of the nose assembly contains the rotor R and escapement mechanism of the patent referred to modified only by the provision of an instantaneous powder train in the rotor.

In the operation of the apparatus, the fuse arms shortly after launching as shown in FIG. 1A, of the patent referred to. Upon impact with a target, the forward end of cup 14 is deformed or crushed, forcing disc 18 and firing pin 20 rearwardly, the firing pin stabbing primer 162 which is now aligned with the firing pin. The powder train in the rotor is then initiated which, in turn, bursts diaphragm 36 and the end wall of cup 30, initiating the booster charge which ruptures wall 28, initiating the war head charge (not shown).

Obviously many modifications and variations of the present invention are possible in the light of the above teachings.

What is claimed is:

1. In an elongated missile of the type having a nose ogive containing a booster charge, an axially moveable firing pin, an arming mechanism interposed therebetween containing a powder train adapted to be moved into axial alignment with the firing pin and booster charge, the improvements comprising:

an extended cylindrical portion at the forward end of the ogive;

a firing pin actuator comprising a deformable tubular member having a rear portion extending down and around the outside of the forward end of said cylindrical portion and aflixed thereto;

a forwardly projecting portion of the tubular member being closed by a flat end wall;

said forwardly projecting portion being deformable upon impact for movement rearwardly;

a disc disposed adjacent the inner surface of the end wall;

said disc being retained adjacent the inner surface of said end wall by a plurality of angularly spaced depressions in said forwardly extending portion of said tubular member; and

a firing pin aflixed to the disc disposed adjacent the inner surface of said end wall.

2. Apparatus in accordance with claim 1 wherein the rear edge of said tubular member is deformed into a cannelure in said cylindrical portion.

References Cited UNITED STATES PATENTS BENJAMIN A. BORC-HELT, Primary Examiner GERALD H. GLANZMAN, Assistant Examiner 

